Avaliação da função renal em pacientes com esquistossomose hepatoesplênica compensada

Abstract

Background - The glomerular involvementin schistosomiasis is well documented, especially in patients with hepatosplenic disease. The aim of this study is to investigate the occurrence of renal abnormalities among patients with HSS, especially tubular disorders. Methods - This is a cross-sectional study with 20 consecutive patients with HSSfollowed in a medical center in Maceió, Alagoas, Brazil. Urinary acidification and concentration tests were performed using calcium chloride (CaCl2) and DDAVP, respectively, and after a 12h period of water and food deprivation. The biomarker MCP-1 was quantified in urine. Fractional excretion of sodium (FENa+), fractional excretion of magnesium (FEMg++) and fractional excretion of potassium (FEK+), transtubular potassium gradient (TTKG) and solute free water reabsorption (TcH2O) were calculated by standard formulae. The HSS group was compared to a group of 17 healthy volunteers (control group). Results - Patient`s average age and gender were similar to controls. Urinary acidification deficit was found in 9 HSS patients (45%), who presented urinary pH > 5.5 after CaCl2 test. Urinary osmolality was significantly lower in HSS patients (588 ± 112 vs. 764 ± 165 mOsm/kg, P =0,001) after 12h period water deprivation. Urinary concentration deficit was found in 85% of HSS patients. The values of MCP-1 were higher in HSS group than control group (122 ± 134 vs. 40 ± 28 pg/mg-Cr, P = 0.01) and positively correlated with the values of microalbuminuria and proteinuria in the HSS group. TcH2O was lower in HSS patients (0.72 ± 0.5 vs. 1.1 ± 0.3, P = 0.04). Conclusions - HSS is associated with important kidney disorders. The main abnormalities found were urinary acidification and concentration defect, indicating the occurrence of tubular dysfunction. There was also an increase in urinary MCP-1, which appears to be a more sensitive marker of renal injury that microalbuminuria.